PFAS Mixture Composition and Internal Exposure Profiles Shape Biological Responses under Field-Realistic Exposure

Authors

• Alan M. Vajda, University of Colorado Denver
• Jill A. Jenkins, U.S. Geological Survey , Wetland and Aquatic Research Center
• David W. Bertolatus, Adams State University
• Denis R. LeBlanc, U.S. Geological Survey , New England Water Science Center
• Christopher J. Martyniuk, University of Florida
• Zachary R. Hopkins, U.S. Geological Survey , Eastern Ecological Science Center
• Andrea K. Tokranov, U.S. Geological Survey , New England Water Science Center
• Abigail R. Dethloff, University of Florida
• Joseph C. Tucker, University of Colorado Denver
• Rainer Lohmann, University of Rhode IslandFollow
• Larry B. Barber, U.S. Geological Survey , Boulder, Colorado

Document Type

Article

Date of Original Version

5-24-2026

Abstract

Per- and polyfluoroalkyl substances (PFAS) occur as complex mixtures, yet mixture-dependent biological effects under environmentally realistic exposure conditions remain poorly understood. We conducted multiyear (2018, 2019, 2021) continuous-flow, field-based exposures of male fathead minnows (Pimephales promelas) using a low-PFAS reference well (REF; sum of measured PFAS (∑PFAS) 0.1–0.2 μg L^–1) and PFAS-contaminated groundwater from a fire-training area (FTA) at Joint Base Cape Cod, Massachusetts. Dilution treatments enabled separation of concentration and mixture effects. Groundwater from well FTA1 was perfluorooctanesulfonate (PFOS) dominated (∑PFAS 10–31 μg L^–1), whereas groundwater from well FTA2 had higher concentrations and was enriched in perfluorooctanoate (PFOA) and diverse precursors (∑PFAS ∼ 80 μg L^–1). Despite comparable plasma ∑PFAS and PFOS in FTA1–100% and FTA2–50% on day-7, cumulative mortality reached approximately 35% in FTA2–50% and 17% in FTA2–100%, and secondary sex trait expression was reduced by approximately 65–80% relative to REF, whereas sperm motility effects were mixture- and time-dependent. Plasma PFAS profiles were dominated by perfluorohexanesulfonate (PFHxS), PFOS, and sulfonamide precursors. Liver transcriptomics from REF-acclimated fish revealed robust disruption of metabolic, mitochondrial, and endocrine pathways that link PFAS mixture chemistry and internal exposure profiles to organismal outcomes, and testis transcriptomics provided complementary insight into reproductive impairment. These results indicate that PFAS mixture composition and internal exposure profiles, including precursor-associated differences, are important determinants of ecotoxicological outcomes under field-realistic conditions.

Publication Title, e.g., Journal

Environmental Science and Technology

Volume

60

Issue

22

Citation/Publisher Attribution

Alan M. Vajda, Jill A. Jenkins, David W. Bertolatus, Denis R. LeBlanc, Christopher J. Martyniuk, Zachary R. Hopkins, Andrea K. Tokranov, Abigail R. Dethloff, Joseph C. Tucker, Rainer Lohmann, Larry B. Barber; PFAS Mixture Composition and Internal Exposure Profiles Shape Biological Responses under Field-Realistic Exposure. Environ. Sci. Technol. 9 June 2026; 60 (22): 15656–15668. https://doi.org/10.1021/acs.est.6c01726

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.